'Hot Spots' No Threat for Pacemakers
Wireless Networks Also Don't Affect Defibrillators Implanted in Heart Patients
Nov. 17, 2006 (Chicago) -- People implanted with pacemakers or
defibrillators to protect them from life-threatening, abnormal heart rhythms
have one less thing to worry about -- being zapped at a wireless hot spot.
"We were unable to see any impact of the wireless systems on the
operation of the pacemakers or the automatic implantable defibrillators,"
researcher Fritz Mellert, MD, says of his study, presented here at the annual
meeting of the American Heart Association (AHA). Mellert is a consultant
cardiac surgeon at the Klinik und Poliklinik for Herzchirugie, at the
University of Bonn, in Germany.
"In no case did a pacemaker stop pacing when it should or pace when it
shouldn't," Mellert tells WebMD. "And none of the implanted
defibrillators gave a shock when they shouldn't, or didn't fire when they
In the study, researchers placed 25 different types of pacemakers and 22
different types of defibrillators in a device simulating the human body.
Each was then exposed to the 1,000 megawatts of transmitting power
authorized in the U.S., as well as to the lower 100-megawatt transmitters used
Five pacemakers tested within 24 inches of the high-frequency transmitters
did experience minor scrambling of monitoring signals, creating some noise,
"but it would not have interfered with their operation," says
None of the defibrillators was affected by data transmissions.
While some airports and restaurants post signs, "people often don't know
when they are close to a wireless hot spot," Mellert says. "Since these
systems are being set up everywhere -- in offices, restaurants, hospitals, and
homes -- these findings should offer some reassurance."
Elliott M. Antman, MD, an AHA spokesman and a heart specialist at Harvard
Medical School, says "a lot of people given pacemakers or implanted
defibrillators are given very strict information about things they need to be
"If we can reduce the number of environmental factors that they need to
worry about, they will have a greater sense of comfort with their device,"
Antman tells WebMD. "This would improve their quality of life."